a15d7e31d4
<!-- The default pull request template is for types feat, fix, or refactor. For other templates, add one of the following parameters to the url: - template=docs.md - template=other.md --> ## Description ref: #9585 This PR if the 1st step (out of 2) in the #9585 refactor. It transforms baseapp's ABCI {Check,Deliver}Tx into middleware stacks. A middleware is defined by the following interfaces: ```go // types/tx package type Handler interface { CheckTx(ctx context.Context, tx sdk.Tx, req abci.RequestCheckTx) (abci.ResponseCheckTx, error) DeliverTx(ctx context.Context, tx sdk.Tx, req abci.RequestDeliverTx) (abci.ResponseDeliverTx, error) SimulateTx(ctx context.Context, tx sdk.Tx, req RequestSimulateTx) (ResponseSimulateTx, error) } type Middleware func(Handler) Handler ``` This Pr doesn't migrate antehandlers, but only baseapp's runTx and runMsgs as middlewares. It bundles antehandlers into one single middleware (for now). More specifically, it introduces the 5 following middlewares: | Middleware | Description | | ----------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | | RunMsgsTxMiddleware | This middleware replaces the old baseapp's `runMsgs`. | | LegacyAnteMiddleware | This middleware is temporary, it bundles all antehandlers into one middleware. It's only created for the purpose of breaking the refactor into 2 pieces. **It will be removed in Part 2**, and each antehandler will be replaced by its own middleware. | | IndexEventsTxMiddleware | This is a simple middleware that chooses which events to index in Tendermint. Replaces `baseapp.indexEvents` (which unfortunately still exists in baseapp too, because it's used to index Begin/EndBlock events) | | RecoveryTxMiddleware | This index recovers from panics. It replaces baseapp.runTx's panic recovery. | | GasTxMiddleware | This replaces the [`Setup`](https://github.com/cosmos/cosmos-sdk/blob/master/x/auth/ante/setup.go) Antehandler. It sets a GasMeter on sdk.Context. Note that before, GasMeter was set on sdk.Context inside the antehandlers, and there was some mess around the fact that antehandlers had their own panic recovery system so that the GasMeter could be read by baseapp's recovery system. Now, this mess is all removed: one middleware sets GasMeter, another one handles recovery. | --- ### Author Checklist *All items are required. Please add a note to the item if the item is not applicable and please add links to any relevant follow up issues.* I have... - [x] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title - [x] added `!` to the type prefix if API or client breaking change - [x] targeted the correct branch (see [PR Targeting](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#pr-targeting)) - [x] provided a link to the relevant issue or specification - [ ] followed the guidelines for [building modules](https://github.com/cosmos/cosmos-sdk/blob/master/docs/building-modules) - [x] included the necessary unit and integration [tests](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#testing) - [x] added a changelog entry to `CHANGELOG.md` - [x] included comments for [documenting Go code](https://blog.golang.org/godoc) - [ ] updated the relevant documentation or specification - [x] reviewed "Files changed" and left comments if necessary - [ ] confirmed all CI checks have passed ### Reviewers Checklist *All items are required. Please add a note if the item is not applicable and please add your handle next to the items reviewed if you only reviewed selected items.* I have... - [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title - [ ] confirmed `!` in the type prefix if API or client breaking change - [ ] confirmed all author checklist items have been addressed - [ ] reviewed state machine logic - [ ] reviewed API design and naming - [ ] reviewed documentation is accurate - [ ] reviewed tests and test coverage - [ ] manually tested (if applicable) |
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.. | ||
api | ||
cmd | ||
config | ||
grpc | ||
mock | ||
rosetta | ||
types | ||
README.md | ||
constructors_test.go | ||
doc.go | ||
export.go | ||
export_test.go | ||
init.go | ||
init_test.go | ||
logger.go | ||
pruning.go | ||
pruning_test.go | ||
rosetta.go | ||
start.go | ||
test_helpers.go | ||
tm_cmds.go | ||
util.go | ||
util_test.go |
README.md
Server
The server
package is responsible for providing the mechanisms necessary to
start an ABCI Tendermint application and provides the CLI framework (based on cobra)
necessary to fully bootstrap an application. The package exposes two core functions: StartCmd
and ExportCmd
which creates commands to start the application and export state respectively.
Preliminary
The root command of an application typically is constructed with:
- command to start an application binary
- three meta commands:
query
,tx
, and a few auxiliary commands such asgenesis
. utilities.
It is vital that the root command of an application uses PersistentPreRun()
cobra command
property for executing the command, so all child commands have access to the server and client contexts.
These contexts are set as their default values initially and maybe modified,
scoped to the command, in their respective PersistentPreRun()
functions. Note that
the client.Context
is typically pre-populated with "default" values that may be
useful for all commands to inherit and override if necessary.
Example:
var (
initClientCtx = client.Context{...}
rootCmd = &cobra.Command{
Use: "simd",
Short: "simulation app",
PersistentPreRunE: func(cmd *cobra.Command, _ []string) error {
if err := client.SetCmdClientContextHandler(initClientCtx, cmd); err != nil {
return err
}
return server.InterceptConfigsPreRunHandler(cmd)
},
}
// add root sub-commands ...
)
The SetCmdClientContextHandler
call reads persistent flags via ReadPersistentCommandFlags
which creates a client.Context
and sets that on the root command's Context
.
The InterceptConfigsPreRunHandler
call creates a viper literal, default server.Context
,
and a logger and sets that on the root command's Context
. The server.Context
will be modified and saved to disk via the internal interceptConfigs
call, which
either reads or creates a Tendermint configuration based on the home path provided.
In addition, interceptConfigs
also reads and loads the application configuration,
app.toml
, and binds that to the server.Context
viper literal. This is vital
so the application can get access to not only the CLI flags, but also to the
application configuration values provided by this file.
StartCmd
The StartCmd
accepts an AppCreator
function which returns an Application
.
The AppCreator
is responsible for constructing the application based on the
options provided to it via AppOptions
. The AppOptions
interface type defines
a single method, Get() interface{}
, and is implemented as a viper
literal that exists in the server.Context
. All the possible options an application
may use and provide to the construction process are defined by the StartCmd
and by the application's config file, app.toml
.
The application can either be started in-process or as an external process. The former creates a Tendermint service and the latter creates a Tendermint Node.
Under the hood, StartCmd
will call GetServerContextFromCmd
, which provides
the command access to a server.Context
. This context provides access to the
viper literal, the Tendermint config and logger. This allows flags to be bound
the viper literal and passed to the application construction.
Example:
func newApp(logger log.Logger, db dbm.DB, traceStore io.Writer, appOpts server.AppOptions) server.Application {
var cache sdk.MultiStorePersistentCache
if cast.ToBool(appOpts.Get(server.FlagInterBlockCache)) {
cache = store.NewCommitKVStoreCacheManager()
}
skipUpgradeHeights := make(map[int64]bool)
for _, h := range cast.ToIntSlice(appOpts.Get(server.FlagUnsafeSkipUpgrades)) {
skipUpgradeHeights[int64(h)] = true
}
pruningOpts, err := server.GetPruningOptionsFromFlags(appOpts)
if err != nil {
panic(err)
}
return simapp.NewSimApp(
logger, db, traceStore, true, skipUpgradeHeights,
cast.ToString(appOpts.Get(flags.FlagHome)),
cast.ToUint(appOpts.Get(server.FlagInvCheckPeriod)),
baseapp.SetPruning(pruningOpts),
baseapp.SetMinGasPrices(cast.ToString(appOpts.Get(server.FlagMinGasPrices))),
baseapp.SetHaltHeight(cast.ToUint64(appOpts.Get(server.FlagHaltHeight))),
baseapp.SetHaltTime(cast.ToUint64(appOpts.Get(server.FlagHaltTime))),
baseapp.SetInterBlockCache(cache),
baseapp.SetTrace(cast.ToBool(appOpts.Get(server.FlagTrace))),
)
}
Note, some of the options provided are exposed via CLI flags in the start command
and some are also allowed to be set in the application's app.toml
. It is recommend
to use the cast
package for type safety guarantees and due to the limitations of
CLI flag types.